The two pictures I showed above would really not be my ideal solution.
I am developing a training tool where a user will match a second hand position (controlled by them) to a ghost-like target position (which will be placed in various positions).
The transparency doesn't look very good with the hard edges in the interior (shown in my first post) so I was wondering if there was a way to blur them using shaders rather than get rid of them entirely.
When I looked at shaders I got something that looks pretty good with the 'shader viewer' using mtl_envGlass. The problem is it seems that it just makes the object look glassy by painting some transformation of the skycube into the models skin. When other models go through the target ghost hand I would like them to be visible inside the target as if looking through a foggy glass, which means that the shader would need information about other models as well as the background. I am a newbie with shaders so I'd appreciate any advice on if and how this would be possible.